The present application relates generally to semiconductor devices and methods of manufacture, and more specifically to gallium nitride-based devices.
Gallium nitride (GaN) possesses fundamental materials properties that make it an attractive candidate for semiconductor device fabrication. These properties include a large bandgap (˜3.4 eV), which enables high temperature operation, a direct bandgap for fabricating light emitting diodes, the ability to form heterostructures with aluminum and indium, and high saturation velocity and breakdown field strength.
Though significant advances have been made in the development of GaN-based optoelectronic devices, including devices suitable for high power, high frequency and/or high temperature applications, a limitation to improving device efficiency is the presence of various deep traps within GaN, especially traps responsible for a current collapse phenomena in GaN metal-semiconductor field effect transistors. Current collapse occurs when the GaN on-resistance increases and current decreases during the application of high voltage to the device.
In view of the foregoing, it would be advantageous to develop structures and related methods of manufacture that minimize the impact of current collapse in GaN-based devices.